The sensory coding of warm perception


  • R. Paricio-Montesinos
  • F. Schwaller
  • A. Udhayachandran
  • F. Rau
  • J. Walcher
  • R. Evangelista
  • J. Vriens
  • T. Voets
  • J.F.A. Poulet
  • G.R. Lewin


  • Neuron


  • Neuron 106 (5): 830-841


  • Humans detect skin temperature changes that are perceived as warm or cool. Like humans, mice report forepaw skin warming with perceptual thresholds of less than 1°C and do not confuse warm with cool. We identify two populations of polymodal C-fibers that signal warm. Warm excites one population, whereas it suppresses the ongoing cool-driven firing of the other. In the absence of the thermosensitive TRPM2 or TRPV1 ion channels, warm perception was blunted, but not abolished. In addition, trpv1:trpa1:trpm3(-/-) triple-mutant mice that cannot sense noxious heat detected skin warming, albeit with reduced sensitivity. In contrast, loss or local pharmacological silencing of the cool-driven TRPM8 channel abolished the ability to detect warm. Our data are not reconcilable with a labeled line model for warm perception, with receptors firing only in response to warm stimuli, but instead support a conserved dual sensory model to unambiguously detect skin warming in vertebrates.